Study On The Influence Of Freeway Side Environment On Drivers’ Speed Selection

In the process of driving,there are many traffic accidents caused by the unreasonable speed selection of the driver,which is harmful and has aroused wide attention of the society.Roadside environment,as one of the important factors affecting the driver’s speed selection,has been widely and deeply studied.However,due to the various roadside components and complex interaction,it is still necessary to supplement the influence study on slope,guardrail,anti-dazzle facilities and other factors on the driver’s speed selection.To solve the above problems,this paper adopted a combination of simulated driving test,field test and personality attribute questionnaire survey.By analyzing the variation law of the drivers’ actual driving speed with different slope types,guardrail settings and anti-glare facilities,and combining with the speed perception and drivers’ personality attributes,the influence mechanism of different roadside environmental factors on the driver’s speed selection was identified,which can provide theoretical reference for roadside safety design.To obtain the influence analysis index of driver speed choice,20 drivers were recruited publicly.Taking the typical section of G69 Xianxun freeway as the prototype,the road simulation software UC-Win Road was used to build 10 road simulation models with different road side environments.Based on the 6-DOF simulation driving platform,vehicle speed,acceleration and driver perceived speed data were obtained through the simulation driving test,and then the data of driver personality attributes were obtained by questionnaire survey,which laid a foundation for the follow-up research of this paper.By analyzing the difference of drivers’ driving speed in different roadside environment,it was found that the type of slope and the position of guardrail have significant influence on the driving speed.The driving speed in deep cutting section is obviously lower than that in embankment section.The distance between the guardrail and the lane edge has a significant positive correlation with the driving speed.And there is no obvious effect of anti-dazzle equipment on the driver’s speed.Then,the influence characteristics of slope type and guardrail position on drivers’ perceived speed were analyzed.The results showed that drivers always overestimate the speed in deep cutting section,while underestimate in embankment section.The distance between guardrail and lane edge has a negative correlation with drivers’ perceived speed.At the same time,through the correlation analysis,it was found that the driver’s perceived speed deviation was negatively correlated with the actual driving speed.Which indirectly proves that the influence mechanism of optical flow rate and edge rate on the driver’s speed perception is correct.Thus,the influence mechanism of slope and guardrail on the driver’s speed choice was obtained,that is,the influence of slope and guardrail on the driver’s speed selection is mainly realized by influencing the driver’s speed perception.To verify the correctness of the mechanism,the drives’ speed selection behavior with different personality attributes was further analyzed.The results showed that although drivers had different personality attributes and different speed values during driving,the influence of roadside environment on drivers’ speed selection was consistent.In addition,drivers with higher scores of neurotic personality were more strongly affected by the roadside environment,while drivers with higher scores of extroversion personality were more inclined to drive at high speed.Finally,the field driving test was carried out to verify the research results.And the results showed that the field test results were basically consistent with the simulation test,and the maximum error occurs in the deep cutting section(the average speed difference between the two tests was 5km/h).The results of this research can help professional and technical personnel in the transportation field to deeply understand the speed selection mechanism of drivers,and provide theoretical reference for further research on the drivers’ speed selection behavior.